The present invention relates to agricultural implements and, in particular, the present invention relates to towable folding wheel rakes useful to form windrows from cut forage.
For many years it has been a typical agricultural process to cut forage, allow some drying to occur, rake it into piles where some additional drying occurs, collect and store it at a desirable moisture content, and subsequently feed such stored, dried forage to livestock. Weather conditions between the time of cutting and collecting play a major role in determining the resulting quality of the product of this agricultural process. In modern times, as farms have grown dramatically in area and the work force reduced in number, the process has been altered to employ power equipment to rake the drying cut forage into long, continuous windrows, which also encourages drying. The windrows may or may not be formed into bales prior to collection. Weather continues to be a major determinant of the overall outcome and the capability to rapidly rake a large field area in a short time is often critical.
Most modern power equipment for raking cut forage employs rotating tined wheels and most particularly banks of rotating tined wheels which are moved through a field of cut forage to form windrows. These banks of wheel rakes and more importantly multiple banks of wheel rakes can be quite wide to reduce the number of passes and thereby decrease the time required to rake a field. Wide rakes thereby provide a time and cost savings to agriculture and enhance the opportunity to perform the raking process so as to best utilize favorable weather conditions. Wide rakes, however, are a challenge to transport between fields.
in response to the transport challenge, wide rakes which fold to facilitate transport over highways and through fence gates have become popular in recent years. Peeters in U.S. Pat. Nos. 5,199,252 and 5,305,509 discloses an exemplary folding hay rake. The Peeters rake involves a towable primary transport frame with right and left secondary frames pivotally deployed from the rear end of the primary frame by action of a telescoping extension assembly. Each of the secondary frames has a bank of wheel rakes.
However, a drawback of such folding rake units can be observed when only one of the two deployed rake banks encounters extreme resistance during the raking of a field. Such resistance might be encountered, by way of example, in the form of an obstruction or an excessively large clump of cut forage. The unevenly encountered resistance results in a temporary delay of one of the rake banks. The primary frame then accumulates stress, resiliently twists or bends slightly in response, and the implement temporarily follows an unintended pathway through the field. Once the uneven delaying resistance has been passed, the two opposed rake banks again provide equal stress to the primary frame, relieving the temporary twist or bend on the primary frame and the implement begins to resume its intended pathway behind the tow vehicle. However, a fishtail pathway has occurred and must be accommodated on a subsequent pass by the tow vehicle operator.
Typically, the tow vehicle operator will increase the overlap of the subsequent pass through the field and optionally reduce the towing speed in response to the fishtail pathway. Both of these responses fail to utilize the potential efficiency of a wide raking implement. Additionally, the stress on the implement framing is undesirable in that the useful life of implement is reduced and the frequency of breakdowns is increased.
Increasing the frame members sizes to stiffen the implement frame is an unacceptable solution to this problem because of increased manufacturing cost and increased implement weight. A more expensive implement which requires more fuel input to a larger tow vehicle for operation due to increased weight again fails to exploit the potential efficiency of wide folding rakes.
The present invention provides an ingenious solution to reduce fishtailing and detrimental uneven frame stress. The present invention is compatible with the use of relatively fine frame members on the agricultural implement, which tends to minimize the implement's weight and does not result in excessive increases in manufacturing costs. The agricultural implement of this invention therefore allows better exploitation of the potential efficiency of a wide folding wheel rake. Further, other aspects of the present invention provide versatility and fine adjustments in forage raking operations.